Everett detectives use digital forensics to track down criminals

EVERETT — The digital video recorder was charred from the heat and drenched from the high-powered hoses used to extinguish the blaze at Emory’s Restaurant at Silver Lake.

The Everett police detectives brought the soggy mess back to the lab. It would take them weeks of tedious work in 2009 to recover the video footage stored on the hard drive.

Eventually the computer would give up images of the 16-year-old arsonist, who caused more than $2 million in damage and left dozens of people out of work. The boy was identified after the images were released and people who recognized the teen called police.

For detectives and a civilian specialist inside the Everett Police Department’s forensics investigations unit, pulling evidence from damaged computers is just part of a complicated job that is constantly changing.

“We have more work than we can handle,” detective Steve Paxton said.

The investigators are tasked with uncovering information stored in cellphones, surveillance systems, home computers, cameras and whatever other popular devices are on the market. They recover emails, photographs, text messages and video and audio footage, all documenting the lives of suspects, witnesses and victims. They also photograph crime scenes.

They help identify bank robbers and shoplifters, lifting still images from surveillance cameras that capture the comings and goings at businesses. They help prosecute people who download child porn from the Internet and store it on cellphones. They recover threatening text messages to hold abusers accountable. They can map a person’s location at a given time by researching cellphone signals captured by cell towers.

The workload has increased as technology becomes more accessible. Most businesses in the city, big or small, use security cameras. People install them at their homes. Some of the systems are outdated and poor quality, which can be an extra challenge. Others are newer and provide crystal clear images.

The increase in surveillance systems is dwarfed in comparison to the proliferation of cellphones.

“Phones have become a very big part of many police investigations,” Paxton said.

In 2011, detectives received 60 requests to examine cellphones for potential evidence. Last year, that number jumped to 168.

The number of cellphones per case also has increased, said Traci Youmans, the unit’s digital imaging analyst. It is common for detectives to obtain search warrants to probe multiple phones connected to suspects or victims.

In one recent case, a man used his cellphone to record himself sexually assaulting his children. The detectives were able to recover the deleted images as well as the metadata documenting when the pictures were taken. The images corroborated the statements of the young victims.

In child sex abuse cases, there is rarely any forensic or medical evidence. It generally comes down to the word of children, Snohomish County deputy prosecutor Matt Baldock said. Their testimony, their memories, often are attacked on the witness stand.

“How can you explain away a video on a phone?” Baldock said.

The man was investigated in the past for sexually assaulting his children. Prosecutors were forced to drop charges when it was clear that his daughters wouldn’t hold up under the pressures of testifying. This time, the girls were able to tell their side of the story and prosecutors were able to show jurors the images. The man was sentenced to more than 40 years in prison.

“Usually it’s not the one thing we find. It’s pulling the whole picture together,” Youmans said.

She and the detectives also must be able to present the information to other detectives, prosecutors and jurors in a way that is easy to track and understand.

“All these gadgets are useless unless we have people who are trained to use them and then to testify,” Sgt. James Collier said.

Right now the unit is made up of Youmans and two detectives. Longtime detective Jeff Shattuck recently retired, after spending years in the unit and launching the lab.

A large part of the challenge is keeping up with the ever-changing technology: tablet computers replacing desktop versions and cloud-based file-sharing instead of hard drives.

There’s hundreds of thousands of dollars invested in equipment and training. It’s an ongoing fight to keep up. The investigators belong to associations and keep up with trade journals. They rely on training to try to keep up with latest.

“It’s law enforcement in the 21st and 22nd century. You have to have the technology,” Collier said.